Trigger, is an open source rally game for you to try. You can create your own level by tweaking the code. Small in size but still a fun game to play. The graphic of the game pretty nice and it will work for Windows, Linux and MacOS X.

Below is a demo of Triger from Google Video.

You can also download maps from the website and Trigger will read the zip file without a need to unzip it. If you want a nice rally racing game, get Trigger because Jamloceng says so.